1. Field of the Invention
This invention relates to exercising apparatus. More specifically, it relates to a large board adapted for use as a surfboard equipped with a fin below the board and a vertical lever arm extending above and below the board and adapted to move one end of the fin upward and downward.
2. State of the Prior Art
A number of patents disclose propelling devices attached to boats, which devices are actuated by a lever arm extending upward from the bottom of the boat. However, none of these patents disclose the use of fins which have one end of the fin actuated in upward and downward motions. Such patents include U.S. Pat. Nos. 923,283, 1,677,847, 3,369,517 and 4,214,547.
U.S. Pat. No. 3,256,850 discloses a "watercraft" propulsion means. The watercraft resembles a surf board but the propulsion means is a hinged device attached to the rear of the watercraft. The hinged arrangement allows this means to fold upon downward movement in the water and to flatten out upon upward movement so as to provide the propelling force. There are no fins disclosed in this reference.